Reigning eventing world champion Sandra Auffarth started out her second Olympic Games in excellent style, laying down a lovely test on Opgun Louvo to take the lead before the break on the first day of eventing dressage. A mistake in the flying changes kept the German rider from breaking into the 30s, but she sits on a mark of 41.6.

The competitors at the Olympic Games ride a modified version of the FEI eventing four-star test B.

“I was very pleased with the test, he was in very good form,” said Auffarth. “It was a good test, but I was a bit annoyed at the mistake. But it was my mistake. I waited a bit too long because he was so fresh.”

The 2015 Pau CCI**** (France) winner, Astier Nicolas, and his Pony Club mount Piaf de B’Neville slipped in just behind Auffarth on a score of 42 penalty points, but he wasn’t satisfied with his result thanks to a mistake in the changes.

“I’m a little disappointed, but I think I should stop being so hard on myself,” said Nicolas, 27. “It’s taken three years to learn the changes, and some days he worries a little bit. I could have done them without mistakes. When he does them well he does them to a very high quality. It’s either black or white.”

He counted on his 7-year partnership with his horse at the Olympic Games.

“I’ve had the horse so long, he feels great,” he said. “He’s a very good friend of mine. He’s very generous and has given me all my biggest victories.”

Australian Sam Griffiths and the Irish-bred Paulank Brockagh slotted into third (46.3), but he wasn’t disappointed with the test.

“My horse went really well,” he said. “My personal best is a few marks below that, but I think they’re judging pretty tough out there.

“There’s some atmosphere out there, but she’s used to going in some pretty big arenas and she handled it really well and I was pleased with that.”

U.S. pathfinder Boyd Martin, mounted on one of two known off-the-track Thoroughbreds in the competition, was pleased with Blackfoot Mystery’s test in the arena, but still sees room for improvement. He sits seventh at the moment (47.7). A few cheers from the crowd set “Big Red” on edge.

“My horse would be the greenest horse on the U.S. team, but he’s a good galloper, and it made sense to put him out first,” said Martin, 36. “We can expect three better scores from the United States after my guy. I couldn’t have asked for much more, it’s about where he is in his training.

“He’s still on the inexperienced side of things, and he did get a bit excited at the cheering, but he kept his cool and did a pretty good job,” he said. “I was trying to work out if it was going to play into my favor or not. Sometimes he needs a little something to pep him up, but he got a little bit anxious, especially in the walk, which was usually our biggest scoring movement. But I was thrilled; there were no big mistakes. I don’t think I got any 4s or 5s.”

The afternoon competition kicks off at 1:30 local time. There are several heavy hitters still to come this afternoon, including reigning Olympic champion Germany’s Michael Jung (Sam FBW), Great Britain’s William Fox-Pitt (Chilli Morning), and the United States’ Clark Montgomery and Loughan Glen so check back for a report later.

Eventing dressage competition continues tomorrow.

Mollie Bailey and Lindsay Berreth are on the ground in Rio de Janeiro for the Chronicle and will be reporting with all the news, fantastic photos and behind-the-scenes details all posted on www.coth.com. Your go-to page for all things Olympic is http://www.chronofhorse.com/2016-Olympics

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